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This work presents the initial results of the drift-scan observation for the neutral hydrogen (HI) intensity mapping survey with the Five-hundred-meter Aperture Spherical radio Telescope (FAST). The data analyzed in this work were collected in night observations from 2019 through 2021. The primary findings are based on 28 hours of drift-scan observation carried out over seven nights in 2021, which covers $60\,{\rm deg}^2$ sky area. Our main findings are: (i) Our calibration strategy can successfully correct both the temporal and bandpass gain variation over the $4$-hour drift-scan observation. (ii) The continuum maps of the surveyed region are made with frequency resolution of $28$ kHz and pixel area of $2.95\,{\rm arcmin}^2$. The pixel noise levels of the continuum maps are slightly higher than the forecast assuming $T_{\rm sys}=20\,{\rm K}$, which are $36.0$ mK (for 10.0 s integration time) at the $1050$--$1150$ MHz band, and $25.9$ mK (for 16.7 s integration time) at the $1323$--$1450$ MHz band, respectively. (iii) The flux-weighted differential number count is consistent with the NRAO-VLA Sky Survey (NVSS) catalog down to the confusion limit $\sim7\,{\rm mJy}/{\rm beam}^{-1}$. (iv) The continuum flux measurements of the sources are consistent with that found in the literature. The difference in the flux measurement of $81$ isolated NVSS sources is about $6.3\%$. Our research offers a systematic analysis for the FAST HI intensity mapping drift-scan survey and serves as a helpful resource for further cosmology and associated galaxies sciences with the FAST drift-scan survey., Comment: 26 pages, 26 figures, and 4 tables

The absorption features in spectra of high-redshift background radio sources, caused by hyperfine structure lines of hydrogen atoms in the intervening structures, are known collectively as the 21-cm forest. They provide a unique probe of small-scale structures during the epoch of reionization, and can be used to constrain the properties of the dark matter (DM) thought to govern small-scale structure formation. However, the signals are easily suppressed by heating processes that are degenerate with a warm DM model. Here we propose a probe of both the DM particle mass and the heating history of the Universe, using the one-dimensional power spectrum of the 21-cm forest. The one-dimensional power spectrum measurement not only breaks the DM model degeneracy but also increases the sensitivity, making the probe actually feasible. Making 21-cm forest observations with the upcoming Square Kilometre Array has the potential to simultaneously determine both the DM particle mass and the heating level in the early Universe, shedding light on the nature of DM and the first galaxies., Comment: 53 pages, 6 figures, 2 extended data figures, 9 supplementary figures. Published in Nature Astronomy

Paper and plastic bags have been mainly used in fruit bagging of pineapple production. However, they are often discarded as agricultural wastes after harvest of pineapple fruit and threaten environment. In this study, effects of white non-woven fabric bag, expandable polyethylene bag, black plastic bag and kraft paper bag on fruit quality of pineapple cv. ‘MD-2’ were investigated. Results showed that fruits with fruit bagging showed no sunburn. When expandable polyethylene bag was used, fruits of pineapple cv. ‘MD-2’ showed better external qualities, nutrition qualities and texture properties. Expandable polyethylene bag made of degradable and recyclable materials could be recommended as a promising practice to reduce agricultural waste in pineapple production. RESUMO: Sacos de papel e plástico têm sido usados principalmente no ensacamento de frutas na produção de abacaxi. No entanto, eles são frequentemente descartados como resíduos agrícolas, após a colheita da fruta do abacaxi, e ameaçam o meio ambiente. Neste estudo, os efeitos da sacola de tecido, não tecido branco, sacola de polietileno expansível, sacola plástica preta e sacola de papel artesanal na qualidade do fruto do abacaxi cv. ‘MD-2’ foram investigados. Os resultados mostraram que as frutas ensacadas não apresentaram queimaduras solares. Quando foi utilizada a bolsa de polietileno expansível, as frutas de abacaxi cv. ‘MD-2’ mostraram melhores qualidades externas, qualidades nutricionais e propriedades de textura. O saco de polietileno expansível feito de materiais degradáveis e recicláveis pode ser recomendado como uma prática promissora para reduzir o desperdício agrícola na produção de abacaxi.

Chemotherapy resistance exposes patients to side effects and delays the effect of therapy in patients. So far, there are no predictive tools to predict resistance to chemotherapy and select sensitive chemotherapeutic drugs for the patient. Here, we aim to develop an in-vitro primary cell culture model from breast cancer patients to predict sensitivity to chemotherapy. We created the primary breast cancer cell medium BCMI and culture system with higher efficiency of the model establishment. Immunofluorescence staining of ERa, PR and HER2 were done to identify the primary breast cancer cell from the counterpart breast cancer patient. The killing assay showed that these primary breast cancer cells responded differently to doxorubicin and pirarubicin treatment. These results indicate that our established primary breast cancer cell model holds great promise for predicting breast cancer sensitivity to chemotherapy drugs.

Purpose The purpose of this study is to study the pitting caused by Ca-Al-O-S composite inclusions of low-alloy steel in 3 Wt.% NaCl solution and 0.01M NaHSO3 solution. Design/methodology/approach The corrosion in 0.01M NaHSO3 was much weaker than in 3 Wt.% NaCl 3D display of the pitting formation and development process that has been calculated using scanning electron microscope (SEM) and laser scanning confocal microscopy (LSCM). In addition, a corrosion mechanism of pitting formation by galvanic interaction of composite inclusion and base metal has been proposed. Findings Results show that in immersion test, metal base around inclusions was dissolved due to corrosion. Corrosion on the metal base closer to inclusions was more severe. Originality/value A corrosion mechanism of pitting formation by galvanic interaction of composite inclusion and base metal has been proposed.

This study aimed to investigate the therapeutic effect of the mucosa-associated lymphoid tissue lymphoma translocation gene 1 (MALT1) on diffuse large B-cell lymphoma (DLBCL) and its underlying molecular mechanism through the application of Z-Val-Arg-Pro-DL-Arg-fluoromethyl ketone (Z-VRPR-FMK). Cultured OCI-LY10 cells and their xenografts in nude mice were treated with Z-VRPR-FMK. The growth and invasiveness of the tumor were observed. The components of the NF-κB signaling pathways, such as P65, MALT1, A20, matrix metalloproteinase 2 (MMP2) and MMP9, were detected using a real-time fluorescent quantitative polymerase chain reaction, immunohistochemical staining, and a Western blot analysis. Z-VRPR-FMK inhibited the growth and invasiveness of OCI-LY10 cells and their xenografts. The increase in the tumor volume was slower in the experimental group than it was in the control group, and the weight of the nude mice was significantly different between the two groups on the 11th and 13th days of treatment. The expression of P65 was significantly lower at the gene level in cultured OCI-LY10 cells and transplanted tumors than in the controls after treatment with Z-VRPR-FMK. The nuclear expression of the P65 protein of xenografts also decreased, but the nuclear expression of the A20 protein followed a reverse pattern. The expressions of the MALT1, MMP2, and MMP9 proteins were lower in the OCI-LY10 cells and transplanted tumors treated with Z-VRPR-FMK compared with the controls. This study indicates that MALT1 might serve as an effective therapeutic target for activated B-cell (ABC)-like DLBCL. Z-VRPR-FMK inhibits the growth and invasiveness of ABC-like DLBCL by depressing the proteolysis of A20, the activation of NF-κB, and the expression of MMP9 and MMP2 induced by the MALT1 protein.

The method of Trojan detection based on the RON (Ring Oscillator Network) has been widely proposed and has a good effect. However, the method needs to integrate a RON on the chip to sense the voltage drop generated by the Trojan. Currently, the number of ROs (Ring Oscillator) required for a RON has not been discussed, which has a large impact on the additional hardware overhead. Therefore, based on the RON for Trojan detection, we propose an optimized layout strategy that can effectively control the number of ROs integrated into the circuit. By measuring the sensing range that can be perceived by a single RO, the sensing radius of the RO is obtained; then, ROs are placed in the circuit in a way of regular hexagonal lattice to clarify the number of ROs required in the network. Determining the appropriate number of ROs not only reduces the hardware overhead required for on-chip integration, but also ensures the reliability of Trojan detection, ensuring seamless coverage of the circuit with as few ROs as possible.

Protoplasts have showed great value for new germplasms generation. A method was described for the isolation of large numbers of pineapple protoplasts. The procedure utilized 5% mannitol solution as the primary osmoticum and an enzyme mixture of 1.5% macerozyme R-10, 1.5% cellulase R-10 and 5% mannitol solution, pH 5.5, followed by differential and gradient centrifugations. Overall, the method was found to be a simplified and effective alternative to those previously described for pineapple protoplast isolation, obtaining the highest protoplast yield (3.6 × 106/g FW) and the highest protoplast viability (88.9%).

By means of the concept of factorial moment the charge transfer rates in DNA segments with fractal structures are investigated. An analytical form for the electron transfer rate is obtained., Comment: 10 pages,2 figures